I would like to add some conditions to my software to limit specific uses without introducing a verbose license. If I switch to MIT can I add my own specific conditions to the software? Is it possible for me to simply update the ISC license to add my own conditions?
Example condition: Wrappers for Magento, WordPress and Drupal upon request only.
With help from commenters and others in this thread I learned the Free Software Foundation calls this Noncopylefted free software and defines it like so:
Noncopylefted free software comes from the author with permission to redistribute and modify, and also to add additional restrictions to it.
According to the selected answer, this kind of software may not be considered "open" nor "free".